Schizophrenia, a chronic disease of central nervous system is a major health problem worldwide. This disease has a lifetime prevalence of 1 percent, is the major cause of admissions to public mental health hospitals and since deinstitutionalization, affects approximately one-third of the homeless population. The etiology is unknown but genetic, environmental and developmental factors are involved. Most investigators believe that schizophrenia is etiologically heterogeneous. The objective of the investigator's program is to test one aspect of the heterogeneity hypothesis for schizophrenia. Using a large epidemiologic sample of patients (the Maryland Epidemiologic Sample (MES)), the investigator now proposes to further our understanding of the etiology of schizophrenia by collecting additional information about the same patients. This is a unique opportunity; in this large epidemiologic sample of schizophrenic patients, possibly the largest ever established in this country, extensive data have already been collected about these patients; and the investigator and his colleagues have demonstrated their ability to conduct multi-disciplinary collaborative research. The investigator now proposes to enrich the existing sample by the addition of newly recruited minority subjects. Evidence indicates that men and women manifest different forms of schizophrenia, with regard to clinical expression, genetic risk and patterns of structural brain changes. There are preliminary data to suggest structural differences in normal male and female brains. The balance of etiologies likely differs between the sexes for schizophrenia. In addition, these etiologic differences appear to interact with normal sexually dimorphic structural brain differences. The investigator plans to quantitate structural brain changes using magnetic resonance imaging (MRI) in thoroughly characterized male and female schizophrenic patients, compared to normal controls. The investigator's aim is to elucidate relationships between structural changes and the heterogeneity of schizophrenia, in a well-described epidemiologic sample, and thus clarify the impact of gender on brain morphology in the illness.